The main issue is having the 3d cache at all helps performance, and for gaming you’d want your game processes exclusively on the CCD with the 3d cache. So either you disable the other CCD (like windows’ game mode feature) or use software to force your game processes onto only the 3d CCD, which effectively turns the CPU into the 9800x3d anyway. Having processes for a single game split between both CCDs can cause jittering. From what I’ve heard, having a 3d cache on the 2nd CCD can eliminate that jittering, removing the need to manually keep game processes on the first CCD.
The main issue is having the 3d cache at all helps performance, and for gaming you’d want your game processes exclusively on the CCD with the 3d cache. So either you disable the other CCD (like windows’ game mode feature) or use software to force your game processes onto only the 3d CCD, which effectively turns the CPU into the 9800x3d anyway. Having processes for a single game split between both CCDs can cause jittering. From what I’ve heard, having a 3d cache on the 2nd CCD can eliminate that jittering, removing the need to manually keep game processes on the first CCD.